Audie asked him if there were any concerns about a human body travelling at this speed.

"Well, mostly, the scientists, they think you cannot maintain your normal freefall position, so it would start flat-spinning," he said. "And if that occurs and it's faster than 150 RPM, there's only one way for your blood to leave your body, and that's through your eyeballs."

Baumgartner and his team are live streaming the jump. We've embedded live video at the bottom of this post. Baumgatner is supposed to step out the capsule at 1:40 p.m. ET.

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